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简介：ThetheoreticalconditionsforthebenddevelopmentorattenuationhavebeenreviewedandtestedforastudyreachoftheMeghnariver.Thefieldobservationsinthenaturalalluvialmeanderdonotsupportthetheoriesdevelopedforbenddevelopment.Thelimitationsofthetheorytoapplyinthenaturalmeanderingriverarediscussed.

简介：NickeliscommonlycoatedontheouterleadsforT8metalpackage.Theleadselectrodepositedbyconventionaldullorbrightnickelover5μmatdirectcurrentfromWattbatharehardtopassthebendfatiguetestforthreetimes.Nickelelectrodepositedatmultiwaveformcurrentincludingdirectcurrent,singleanddoublepulsefromsulfamatebathcanimprovethebendfatiguestrengthofleads.Suchnickelplatinghasamultilayerstructure,itsmorphologyofsublayerscanbeclearlyseeninitscrosssectionwithSEM.Theelectrochemicalstudyshowsthatthesesublayershavedifferentcorrosionpotentials.ThebendfatiguetestofleadswithsuchplatingforT8metalpackageshowsthatthenumberofbendincreaseswiththedecreaseofaveragecurrentdensityofmultiwaveform,whichcanbeattributedtothereductionofeverysublayerthicknessandtheincreaseoflayernumbersunderthesameconditionoftotalthickness.

简介：刺激堤是在河训练的一个重要元素那在流动地，沉积运输和床地形学里创造快速的变化。在隧道拐弯的流动和沉积运输的机制是很复杂的，特别当一个刺激堤在拐弯被构造时。大多数流动行为上的以前的调查并且在刺激堤附近搜索在直隧道被执行。在流动的实验的结果在90度隧道在一个刺激堤附近回答并且搜索的这份报纸弯曲被介绍。有一致谷物尺寸的沙被用作床材料。实验与分泌物的不同价值在拐弯为不同地点和刺激堤的不同长度被进行。在一个刺激堤附近的三块维的流动地被调查。最大的深度搜索在拐弯被相关到弗鲁德数字，长度和刺激堤的地点。

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简介：Theinterplaybetweenstreamwiseflow,curvature-inducedsecondaryflow,sedimenttransportandbedmorphologyleadstotheformationofatypicalbar-poolbedmorphologyinopen-channelbends.Theassociatedscourattheouterbankanddepositionattheinnerbankmayendangertheouterbank'sstabilityorreducethenavigablewidthofthechannel.Previouspreliminarylaboratoryexperimentsinasharplycurvedflumewithafixedhorizontalbedhaveshownthatabubblescreenlocatedneartheouterbankcangenerateanadditionalsecondaryflowlocatedbetweentheouterbankandthecurvature-inducedsecondaryflowandwithasenseofrotationoppositetothelatter.Thisbubble-inducedsecondaryflowredistributesvelocitiesandbedshearstresses.Thereportedstudyinvestigatestheimplicationsofabubblescreenontheflowandthemorphologyinconfigurationswithmobilebed.Velocitymeasurementsshowthatthebubble-inducedsecondaryflowshiftsthecurvature-inducedsecondaryflowininwardsdirectionandreducesitsstrength.Thebubblescreenconsiderablyreducesmorphologicalgradients.Maximumbendscourisreducedbyabout50%andoccursfurtherawayfromtheouterbankwhereitdoesnotendangerthebankstabilityanymore.Thelocationofmaximumscourcoincideswiththejunctionofthecurvature-inducedandbubble-inducedsecondaryflows.Atthissamelocation,themaximumstreamwisevelocitiesandmaximumverticalvelocitiesimpingingonthebedalsooccur,whichindicatestheirimportancewithrespecttotheformationofbendscour.Thebubblescreenalsosubstantiallyreduceddepositionattheinnerbank.Thesepreliminaryexperimentsshowthepotentialofabubblescreentoinfluenceandmodifythebedmorphology.

简介：Ageneralizedbendflowmodel,treatinga90°singlebendand60°continuousbends,wasdesignedtoquantitativelydescribe3-Dturbulencemechanismofcirculatingnot-fully-developedflowinopenchannelswithbends.The3-Dfluctuatingvelocitiesofturbulentflowweremeasuredandanalyzedwitha3-Dacoustic-Dopplervelocimeter.Formulafor3-Dturbulentintensitywasderivedusingthedimensionanalysisapproach.Expressionsofverticalturbulent-intensitydistributionswereobtainedwiththemultivariant-regressiontheory,whichagreewithexperimentdata.Distributionsofturbulentintensityandturbulentstresswerecharacterized,andtheirrelationshipswereconcluded.Inthebend-turbulent-flowcoreregion,longitudinalandlateralturbulent-intensitydistributionsarecoincidentwithlineardistribution,butinnear-wallregionarecoincidentwiththeGammadistribution.VerticalturbulentintensitydistributionsarecoincidentwiththeRayleighdistribution.Herein,itisconcludedthatthebendturbulenceisanisotropic.

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简介：Weproposeanultra-widebandopticaldiodedevicebasedontwo-dimensionalsquare-latticephotoniccrystals.Forthedevice,theoddmodeiscompletelytransmittedinonedirectionandconvertedtothefundamentalevenmode,butcompletelyreflectedintheotherdirection.Theoperationbandwidthofthedeviceispreservedwithinaratherwiderangeoffrequencies,whichisover6.5%ofthecentralfrequency.Adirectionalcouplerand90°bendareutilizedasthecompositefunctiondevicewithmodefilterandmodeconverter.Itispossiblethatthephotoniccrystaldevicecanhelptoconstructon-chipopticallogicaldevicesandbenefitgreatlytotheopticalsystemswithmultiplespatialmodes.更多还原

简介：Understandingbendlossinsingle-ringhollow-corephotoniccrystalfibers(PCFs)isbecomingofincreasingimportanceasthefibersenterpracticalapplications.Whilepurelynumericalapproachesareuseful,thereisaneedforasimpleranalyticalformalismthatprovidesphysicalinsightandcanbedirectlyusedinthedesignofPCFswithlowbendloss.Weshowtheoreticallyandexperimentallythatawavelength-dependentcriticalbendradiusexistsbelowwhichthebendlossreachesamaximum,andthatthiscanbecalculatedfromthestructuralparametersofafiberusingasimpleanalyticalformula.Thisallowsstraightforwarddesignofsingle-ringPCFsthatarebend-insensitiveforspecifiedrangesofbendradiusandwavelength.Italsocanbeusedtoderiveanexpressionforthebendradiusthatyieldsoptimalhigher-ordermodesuppressionforagivenfiberstructure.

简介：有二个串联microring共鸣器和二U弯曲波导的一个XOR/XNOR光逻辑电路被建议。microring共鸣器用电镀物品光的聚合物做的并且通过线性电镀物品光的效果调制。二个电的信号被用于二microrings，并且同时的XOR和XNOR操作在二个不同操作模式被表明。我们也使用散布矩阵方法分析模拟输出系列，并且发现象00和11一样的不同输入能在某些波长在输出系列导致不同扑灭比率，尽管他们的数字产量是一样。

简介：摘要目的观察小鼠脑微血管内皮细胞bEnd.3来源的外泌体对骨髓间充质干细胞(BMSCs)成骨效应的影响。方法通过超高速离心法提取bEnd.3细胞来源的外泌体(b-Exo)，利用透射电子显微镜(TEM)、纳米粒径追踪分析(NTA)和外泌体蛋白标志物蛋白质印迹法(Western blot)实验鉴定所提取的外泌体。与磷酸盐缓冲液(PBS)对照，使用茜素红染色检测其对BMSCs基质矿化，反转录-聚合酶链反应(RT-PCR)检测成骨分化相关基因Runx2、Osteopontin、Osteocalcin表达的影响。组间比较采用t检验。结果TEM下观察到b-Exo具有典型囊泡样结构，NTA显示b-Exo浓度为7.5×1010颗粒/ml，直径为(100.0±7.3) nm。b-Exo可显著增强BMSCs基质矿化，b-Exo组成骨分化相关基因核心结合蛋白因子2(Runx2)、骨桥蛋白(Osteopontin)和骨钙蛋白(Osteocalcin)的表达显著高于对照组(8.28±0.34比3.71±0.40，t＝4.974，P<0.01；9.19±1.91比4.09±0.88，t＝5.562，P<0.01；10.31±1.67比5.32±0.31，t＝5.432，P<0.01)，差异均有统计学意义。结论bEnd.3细胞来源的外泌体能够促进BMSCs的成骨分化，有望应用于骨再生和骨质疏松症的无细胞治疗。

简介：在这，纸试验性的学习导致在上搜索并且流动在在90度隧道拐弯的一个T形状刺激堤附近的地被介绍。实验在一条实验室隧道被进行在一个清楚的水条件下面测量床地形学的变化。三个维的流动领域被声学的Doppler速度计由于一个T形状刺激堤在一个scour洞里测量。它被增加弗鲁德数字和一些刺激堤发现那数量搜索增加。增加刺激堤的翅膀长度减少scour。数量搜索在刺激堤在上游更同样比作那在刺激堤下游。由增加刺激堤的翅膀长度，流动分离的地区膨胀。作为结果，旋涡的尺寸增加。流动地的细节也在纸被探讨。

简介：超离频分子的重量聚乙烯(UHMWPE)纤维/环氧基树脂composites被真空制作处理技术的灌输的帮助树脂(VARI)。composites的治好的条件在80的痊愈温度